📈ap pre-calculus review

Change of base formula

Written by the Fiveable Content Team • Last updated August 2025
Verified for the 2027 exam
Verified for the 2027 examWritten by the Fiveable Content Team • Last updated August 2025

Definition

The logarithmic identity log_b(x) = log_c(x) / log_c(b) that allows conversion of logarithms from one base to another, enabling use of calculators and simplification of expressions.

AP course connection

Topic 2.13: 2.13 Exponential and Logarithmic Equations and Inequalities

Unit 2

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